<?php
	// echo $_GET['username'];

	$user_arr = array('a','b','c');
	if(isset($_GET['username'],$user_arr)){
		if($_GET['username' === 'a']){
			echo json_encode(array(
				'username' => $_GET['username'],
				'url' => 'https://bulma.io/images/bulma-logo.png'
			));
		}else{
			echo json_encode(array(
				'mes':"<h1>没有".$_GET['username']."信息"
			))
		}
	}
?>